THE EFFECTS OF HYPERBARIC AND ISOBARIC BUPIVACAINE ON POST SPINAL HEMODYNAMIC PROFILES AND BLOCK CHARACTERISTICS AMONG PARTURIENTS UNDERGOING ELECTIVE CESAREAN SECTION AT DILLA UNIVERSITY REFERRAL HOSPITAL: A RANDOMIZED CONTROLLED TRIAL STUDY

<strong>Abstract</strong> Background: Cesarean section is an operative technique by which the fetus is delivered through abdominal and uterine incisions. Bupivacaine is a well-known local anesthetic agent that can be available in isobaric and hyperbaric forms and is commonly used during spinal anesthesia for cesarean delivery. The difference in baricity of bupivacaine affects the hemodynamic profiles, extent, and onset of sensory and motor block. Objective: To compare the effects of hyperbaric and isobaric bupivacaine on hemodynamic profiles and block characteristics among parturients undergoing elective cesarean section under spinal anesthesia at Dilla University Referral Hospital from February 10, 2022 to June 10, 2022. Method: After obtaining ethical clearance from the ethical review board, 64 pregnant mothers scheduled for elective cesarean section under spinal anesthesia were randomized to either 12.5 mg of isobaric bupivacaine(n = 32) or 12.5 mg of hyperbaric bupivacaine (n = 32). The normality of data was checked using histogram and Shapiro-Wilk normality tests. Comparisons of numerical variables between study groups were done using the independent t-test and the Mann Whitney U test for symmetric and asymmetric data, respectively. A mixed ANOVA was used for repeated measurements, and a chi-square or Fisher exact test was used for categorical variables. A P value 0.05). The median onset time of maximum sensory block was faster in the hyperbaric group 3(1) minutes than in the isobaric group 4 (2) minutes) (P&lt;0.001). There was also a faster median onset time of maximum motor block in the hyperbaric group 4(2) minutes) compared to the isobaric group 5(2) minutes) (p&lt;0.001). Conclusion and recommendation: We conclude that hyperbaric bupivacaine provides stable intraoperative hemodynamic parameters and an earlier onset of block than isobaric bupivacaine. We recommend to researchers to do further randomized controlled trials, with invasive blood pressure measurement and multicenter study.